Conventionally, there is a vehicle multi-frequency continuous wave (CW) radar device that acquires a velocity and a distance of a target from reflected waves that is obtained when a frequency of transmission waves is changed stepwise (see, for example, Patent Literature 1). Normally, in a vehicle radar device, it is necessary to consider a velocity of an own vehicle in order to acquire a ground velocity of a target. Therefore, this type of radar device acquires velocity information of the own vehicle from, for example, an engine control unit of the vehicle.